In the past, users of vintage juke boxes were content to wait for a short period of time between their selection of a song and the actual initiation of playback because the interval was filled with observable operations of the machine, such as a mechanical arm grasping a record disc, moving it to the turntable location, and dropping the needle. A juke box's song library was printed on pages, often with a flipping mechanism, and each song was assigned an access code such as “J7” or “512”. Music was played back from records. Even today, the large-scale mechanical operations involved in loading a record onto a turntable are visually entertaining, and the audible mechanical movements within a vintage juke box assure a user that the unit is working to prepare a music selection for playback. Moving a record onto a turntable involves considerable mechanical component movement, and a vintage juke box appears to do a very precise job, so most users don't mind waiting for a while to hear music. Juke box systems are still popular, such as those shown and described in U.S. Pat. Nos. 6,031,795 and 6,587,403, but many modern juke boxes use CD's instead of records for the playback of music, which may increase the number of selections available in some systems.
With the advent of digital music compression technology, such as the MP3 and WMA formats, the basic functionality of these juke boxes can now be carried in your pocket. Similar to a DVD player, a common MP3 player generates custom access menus based on the available media content. The difference here is that there is no single file which exists with all the information required to quickly generate the custom access menus, as is found on the DVD. The menu information for MP3 is embedded in each individual media file in multiple fields for artist name, song name, genre, etc., and must be gleaned from all the available files to build a database for a custom access menu. Acquiring all this information can take a great deal of time, especially for a large number of media files. For a user, this delay is an annoying waste of time, but tolerated because of the extraordinary volume of music that will be available from a very compact device. There are no large moving parts that suggest what the device is doing, and the operation of the device is virtually silent, so the only feedback to a user that indicates that the device is working is usually a small LCD screen. Unless the scattered embedded information is stored in permanent memory (or at least non-volatile memory), a user must wait again and again for this information to be rediscovered and processed. MP3 players are frequently updated with new music, which further complicates the process for generating custom access menus, so many MP3 products appear to be so slow that it seems like something is wrong, especially when they are based on CD storage. Every time the disc is changed the custom access menus must be reprocessed. This has contributed to an overall lack of popularity for the CD based format of MP3 players, even though they generally possess larger storage capacity than their flash memory competition. This lack of popularity is also a factor in why commercially produced music CD's in MP3 format are not available.
The Compact Disc Digital Audio (CD-DA) standard was introduced in 1982, and it was formatted as one continuous 70 minute long audio recording. A simple Table Of Contents (TOC) was created such that each track had a time code used by CD players for fast random access to tracks for features such as shuffle. This simple approach allowed a CD to be played almost immediately, which quickly won wide spread approval in the marketplace. This simple access method was also easy to specify and document, allowing a wide and rapid acceptance of the CD-DA format among manufacturers. This initial format allowed only for raw audio data to be stored on the CD, indexed only by time codes in the TOC. Audio format CD's use no filenames or folders, since the format does not provide adequate error correction for the lossless storage of data files. As such, the basic CD-DA format, which can only store 70 minutes of audio, is not suitable for storage of MP3 files.
In order for music CD's in the modern MP3 format to become commercially available that are customized for an MP3 player based juke box, all CD's should operate predictably on all systems. There is currently no standard for pre-storing a database of menu information along with the song files on a CD containing MP3 files. There is also no standard for a method of selecting songs using a simple vintage access code, like “G7”. Standardization should be accomplished with a method that is easy to understand and implement, not a highly technical method for mastering a CD that is only used by a large CD mastering house. An example of an understandable method might be embedding an access code in a new ID3 tag, similar to the song title, etc., but in practice this would require a user to modify hundreds of files to make a custom CD. So much extra work would doom the product architecture to a short and unpopular lifetime, so a better approach that does not require the music files to be modified in any way is needed.